In recent years, various methods for manufacturing an antireflective article which is a film-shaped antireflective article by arranging a number of fine protrusions closely to each other on the surface of a transparent base (transparent film) to prevent reflections have been proposed (see Patent Documents 1 to 3). These methods utilize the properties of a so-called moth-eye structure to change the refractive index to incident light continuously in a thickness distribution of a substrate to eliminate interfaces where the refractive indexes are discontinuous to thereby prevent reflections.
In an antireflective article having this moth-eye structure, fine protrusions are arranged closely to each other so that an interval d between adjacent fine protrusions is no more than a shortest wavelength Λmin of a wavelength band of electromagnetic waves of which reflections are to be prevented (d≦Λmin). Moreover, each fine protrusion is manufactured so that the fine protrusion stands vertically on the transparent base and the cross-sectional area thereof decreases (the fine protrusion is tapered) as the fine protrusion advances from the transparent base toward a distal end.
However, an antireflective article having this type of moth-eye structures has a problem in that the scratch resistance thereof is not sufficient for practical use. That is, for example, when another object comes into contact with the antireflective article, the anti-reflection function deteriorates in a local region, and cloudy spots, scratches, or the like appear in the contacting region, which may cause appearance defects.
Patent Document 1: Japanese Unexamined Patent Application, Publication No. S50-70040
Patent Document 2: Japanese Unexamined Patent Application (Translation of PCT Application), Publication No. 2003-531962
Patent Document 3: Japanese Patent No. 4632589